[Elecraft] KAT100 "HI REFL"

[Sam Binkley]

    When using my KAT100 with my K2/100 I am getting a "HI REFL" message 
on the K2 display.  The tuner will auto tune to 1.0-1.1:1 with no 
problem.  But when I key the transmitter above 50 watts, the message is 
displayed and the output goes to zero.

    I found an open diode at D2 in the SWR bridge circuit of the KAT100. 
  After replacing D1 and D2, inspecting T1 and its connections, and 
recalibrating the SWR bridge, it worked fine yesterday during a one hour 
QSO with my friend in OR.  Last night I tried it and the "HI REFL" 
message came up once again.  The K2/100 works fine into a dummy load and 
while using a manual tuner on an antenna.  Three different antennas give 
similar results on the 80, 40, 30 and 20 meter bands.  I haven't tried 
other bands but assume the results would be the same.

    The K2/100 and KAT100 are grounded via a copper strap, approximately 
7 feet long, to an 8 foot ground rod therefore I don't suspect stray RF. 
  I'm at a loss determining where to check next and would appreciate any 
help.
  73,
  Sam, KL7V/5